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David Alan Gilbert" , tony.luck@intel.com, marcorr@google.com, sathyanarayanan.kuppuswamy@linux.intel.com Subject: Re: [PATCH v7 43/45] virt: Add SEV-SNP guest driver To: Randy Dunlap , x86@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-efi@vger.kernel.org, platform-driver-x86@vger.kernel.org, linux-coco@lists.linux.dev, linux-mm@kvack.org References: <20211110220731.2396491-1-brijesh.singh@amd.com> <20211110220731.2396491-44-brijesh.singh@amd.com> From: Brijesh Singh Message-ID: <38e5047c-43a9-400b-c507-337011e0e605@amd.com> Date: Thu, 11 Nov 2021 13:27:53 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.13.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit X-ClientProxiedBy: MN2PR01CA0023.prod.exchangelabs.com (2603:10b6:208:10c::36) To SN6PR12MB2718.namprd12.prod.outlook.com (2603:10b6:805:6f::22) Precedence: bulk X-Mailing-List: linux-coco@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Received: from [10.236.30.107] (165.204.77.1) by MN2PR01CA0023.prod.exchangelabs.com (2603:10b6:208:10c::36) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4690.15 via Frontend Transport; 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The driver is built if the user enables the AMD memory encryption support. If the user has selected the AMD memory encryption support, they will be querying an attestation report to verify that the guest is running on AMD memory encryption enabled hardware. 2. Typically, an attestation report is retrieved from an initial ramdisk (before mounting the disk). IIUC, the standard initramfs build tools may not include the driver by default and requires the user to go through hoops. However, I have no strong reason to keep it to "y" if other prefers "m". thanks